import copy
def inItems(item,items):
    inIt=False
    v=None
    for i in range(len(items)):
        if items[i]==item:
            inIt=True
            v=items[i]
            items.remove(items[i])
            break
    return(inIt,v)
def bjitems(items,items_chuku):
    items2=copy.copy(items_chuku)
    left=[]
    for item in items:
        (inIt,v)=inItems(item,items2)
        if inIt:
            pass
        else:
            left.append(item)
    return(left,items2)
if __name__=="__main__":
    now=[1,2]
    new=[2,3,4]
    (left,right)=bjitems(now,new)
    print(now,new)
    print(left,right)